Field of the Invention
This invention relates to a venous tourniquet, having a constricting strap that can be placed around a body part and that itself is embodied elastically in a circumferential direction or is provided with at least one elastic portion, and having a closure device by which the constricting strap can be locked in a state in which it is wrapped tightly around a body part, to form a tightening loop.
Discussion of Related Art
One venous tourniquet is disclosed by U.S. Pat. No. 3,930,506. An adhesive portion is applied to an end portion of the constricting strap, for fixation of a tensing loop wrapped around the body part with tensile stress. If this portion is not fixed in the correct position in the first fixation, then reliably fixing it again is not ensured, which can have disadvantages in terms of use. Applying the adhesive also entails corresponding effort.
U.S. Pat. No. 3,628,536 discloses another venous tourniquet that has a closure device with openings, distributed over a length, and with a protrusion attached to one end, which protrusion is adapted to engage openings.
US Patent Application Publication 2012/0071917 A1 discloses a constricting strap device for body parts for preventing severe blood loss in injuries. In this known constricting strap device, a tightening device for attaining high tension of the constricting strap, wrapped into a loop around the body part, and a tension indicator are provided, with which tension indicator a tension of the constricting strap that is generated can be ascertained either in tactile fashion or visually. For example, as shown in FIGS. 14A and 14B and the specification of this document, a tension cloth is folded and fixed in the folded area at fastening locations, which tear if the tension is excessive. The fastening locations can have variously many fastening points over the width of the tension cloth, as a result of which the fastening locations tear if the tensile stress differs accordingly. In any case, a tensile stress this high must not be applied until in order to cause tearing at the fastening location or locations, after which the tensile stress abruptly drops. With these provisions, a metered tension, of the kind that is effective in venous tourniquets, for instance, in order to occlude a venous blood flow, is difficult to achieve and detect. Also, the closure device is relatively complicated.
Further constricting strap devices for body parts are shown in U.S. Pat. No. 5,653,728 A, WO 2006/015987 A1, GB 2 424 189 A, U.S. Pat. No. 6,525,238 B2, US Published Application 2008/0312682 A1, and U.S. Pat. No. 6,250,047 B1. The constricting strap devices are provided with various closure devices, and the locking or fixation is sometimes inconvenient, or the construction is complicated. For example, in U.S. Pat. No. 5,653,728 A and WO 2006/015987 A1, versions of constricting strap devices are also disclosed that can be thrown away after use, of the kind often needed in clinical use for compliance with hygiene regulations.
DE 10 2009 025 416 B4 discloses a supporting or fixation belt with at least one flexible, inelastic portion and fixation devices for fastening belt regions to one another or to orthopedic devices. The fixation devices can be embodied as hook-and-loop closure elements and stitched on, glued, or welded on, or sewn onto ends of a belt strap. The top side of a continuous elastic belt portion can also be equipped with a plush layer, while on the underside, fixation devices for fixing the end regions to one another or to the orthopedic devices are provided. This kind of support or fixation belt with fixation devices in its end regions is not adjustable to variable loop sizes and cannot be used as a venous tourniquet.
Further bandlike belts or belt portions with hook-and-loop closure are shown in EP 2 045 047 A2, GB 479 442 A, and GB 1 033 130 A.